Various devices are known for applying a coating to a conveyor band already installed. Some of them use spray guns by which the liquid coating material (e.g. a bond-breaking agent such as a hydrogenated vegetable oil) is applied to the band surface. Even with several such spray guns, however, it is difficult to obtain a layer of uniform thickness on the conveyor band with the result that goods picking up different amounts of coating material may exhibit irregularities which might cause problems during handling, e.g. upon automatic packaging.
Similar drawbacks, due especially to an uneven conveyor surface, are encountered with another conventional device by which the coating material is dripped onto the upper run of the band and is distributed thereover by a wiper assembly. Such a device, furthermore, limits the space available above the conveyor for the installation of a feeder for the goods to be transported.